1. Field of the Invention
The present invention relates to an inkjet printer.
2. Description of the Related Art
Inkjet printers have characteristics such that a shorter printing time results in a lower image quality and such that realization of a higher image quality requires a longer printing time. Which of the printing time and the image quality should be prioritized varies case by case. Under such circumstances, there are known inkjet printers which are operable in a plurality of printing modes that are different in terms of the printing time and the image quality, so that a user can choose any one of the plurality of printing modes.
For example, printers disclosed in Japanese Laid-Open Patent Publications Nos. Hei 7-329402 and 2001-27941 allow color printing or monochromatic printing to be chosen, and also allow high-precision printing or draft printing to be chosen. Namely, these printers prepare four patterns of printing modes, i.e., color high-precision printing, color draft printing, monochromatic high-precision printing, and monochromatic draft printing. These printers notify the user of the time necessary to perform printing in the chosen printing mode (hereinafter, referred to as the “expected printing time”).
However, conventional printers as described above provide a limited number of printing modes, and may not provide a combination of printing time and image quality desired by the user. In addition, the relationship between the printing time and the image quality is not simple. In some cases, the change amount in the image quality caused by a certain change in the printing time varies in accordance with the printing time. Specifically, there are cases where, in a certain range of printing time, the image quality is not reduced much even when the printing time is shortened; whereas in another range of printing time, the image quality is significantly reduced when the printing time is slightly shortened. In some other cases, the change amount in the image quality caused by a certain change in the printing time varies in accordance with the image or the like to be printed (hereinafter, referred to as the “printing object”). For example, when the printing object is a letter or a character, the image quality may not be reduced much even when the printing time is shortened. By contrast, when the printing object is a photograph, the image quality may be significantly reduced when the printing time is slightly shortened. With the conventional printers, there are only fixed combinations of the printing time and the image quality, and the printing time and the image quality cannot be adjusted in accordance with the inherent characteristics of the printing object. Therefore, the conventional printers cannot satisfy the demands of the user.